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  <title>Document</title>
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<body>
  <script>
    var maximumGap = function (nums) {
      if (nums.length < 2) {
        return 0
      } else {
        nums.sort((a, b) => a - b)
        let num = 0;
        for (let i = 0; i < nums.length; i++) {
          if (nums[i + 1] - nums[i] > num) {
            num = nums[i + 1] - nums[i]
          }
        }
        return num
      }
    }
    console.log(maximumGap([3, 6, 9, 1]));
  </script>
</body>

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